Sphingobacterium endophyticum sp. nov., a novel endophyte isolated from halophyte

Area of Science:

• Microbiology
• Bacterial Taxonomy
• Plant-Microbe Interactions

Background:

• Halophytes, such as Suaeda corniculata, inhabit extreme environments and harbor unique microbial communities.
• The Gurbantunggut desert in China presents a challenging environment for life, necessitating specialized adaptations in its resident microorganisms.

Purpose of the Study:

• To isolate and characterize a novel bacterial strain from the leaves of Suaeda corniculata.
• To determine the phylogenetic and taxonomic position of the novel isolate within the bacterial domain.

Main Methods:

• Isolation of bacteria from Suaeda corniculata leaves.
• Phenotypic characterization including Gram staining, morphology, and growth conditions (temperature, pH, salinity).
• Phylogenetic analysis using 16S rRNA gene sequences and whole-genome data (coding sequences, ANI values).
• Chemotaxonomic analysis (isoprenoid quinones, fatty acids, polar lipids) and DNA G+C content determination.

Main Results:

• A novel Gram-negative, aerobic, rod-shaped bacterium, strain NYYP31^T, was isolated.
• The strain exhibited tolerance to a wide range of temperatures (4-42 °C), pH (5.0-10.0), and salinity (up to 8% NaCl).
• Phylogenetic analyses and low Average Nucleotide Identity (ANI) values (<95-96%) confirmed its status as a new species within the Sphingobacterium genus, proposed as Sphingobacterium endophyticum sp. nov.

Conclusions:

• Strain NYYP31^T represents a novel species, Sphingobacterium endophyticum, isolated from a desert halophyte.
• The findings contribute to the understanding of bacterial diversity in extreme environments and plant-associated microbiomes.